<resources>
  <string name="app_name">ToDo</string>
  <string name="msg_empty">Click the + icon to add a todo item!</string>
  <string name="msg_empty_filtered">Click the + icon to add a todo item, or change your filter to show other items</string>
  <string name="menu_about">About</string>
  <string name="is_completed">Item is completed</string>
  <string name="created_on">Created on:</string>
  <string name="menu_edit">Edit</string>
  <string name="desc">Description</string>
  <string name="notes">Notes</string>
  <string name="menu_save">Save</string>
  <string name="menu_add">Add</string>
  <string name="menu_delete">Delete</string>
  <string name="menu_filter">Filter</string>
  <string name="menu_filter_all">All</string>
  <string name="menu_filter_completed">Completed</string>
  <string name="menu_filter_outstanding">Outstanding</string>
  <string name="oops">Sorry! Something went wrong!</string>
  <string name="report_template"><![CDATA[<h1>To-Do Items</h1>

<h2></h2>
<p><b>COMPLETED</b> &mdash; Created on: </p>
<p></p>

]]></string>
  <string name="menu_share">Share</string>
  <string name="pref_url_title">Web service URL</string>
  <string name="web_service_url_key">webServiceUrl</string>
  <string name="web_service_url_default">https://commonsware.com/AndExplore/2.0/items.json</string>
  <string name="settings">Settings</string>
  <string name="menu_import">Import</string>
  <string name="cancel">Cancel</string>
  <string name="retry">Retry</string>
  <string name="import_error_title">Import Failure</string>
  <string name="import_error_message">Something went wrong with the import!</string>
</resources>

package com.commonsware.todo.ui.roster

import android.content.Intent
import android.net.Uri
import android.os.Bundle
import android.util.Log
import android.view.*
import android.widget.Toast
import androidx.activity.result.contract.ActivityResultContracts
import androidx.fragment.app.Fragment
import androidx.lifecycle.lifecycleScope
import androidx.navigation.fragment.findNavController
import androidx.recyclerview.widget.DividerItemDecoration
import androidx.recyclerview.widget.LinearLayoutManager
import com.commonsware.todo.R
import com.commonsware.todo.databinding.TodoRosterBinding
import com.commonsware.todo.repo.FilterMode
import com.commonsware.todo.repo.ToDoModel
import com.commonsware.todo.ui.ErrorDialogFragment
import com.commonsware.todo.ui.ErrorScenario
import kotlinx.coroutines.flow.collect
import org.koin.androidx.viewmodel.ext.android.viewModel

private const val TAG = "ToDo"

class RosterListFragment : Fragment() {
  private val motor: RosterMotor by viewModel()
  private val menuMap = mutableMapOf<FilterMode, MenuItem>()
  private var binding: TodoRosterBinding? = null

  private val createDoc =
    registerForActivityResult(ActivityResultContracts.CreateDocument()) {
      motor.saveReport(it)
    }

  override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)

    setHasOptionsMenu(true)
  }

  override fun onCreateView(
    inflater: LayoutInflater,
    container: ViewGroup?,
    savedInstanceState: Bundle?
  ): View = TodoRosterBinding.inflate(inflater, container, false)
    .also { binding = it }
    .root

  override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
    super.onViewCreated(view, savedInstanceState)

    val adapter = RosterAdapter(
      layoutInflater,
      onCheckboxToggle = { motor.save(it.copy(isCompleted = !it.isCompleted)) },
      onRowClick = ::display
    )

    binding?.items?.apply {
      setAdapter(adapter)
      layoutManager = LinearLayoutManager(context)

      addItemDecoration(
        DividerItemDecoration(
          activity,
          DividerItemDecoration.VERTICAL
        )
      )
    }

    viewLifecycleOwner.lifecycleScope.launchWhenStarted {
      motor.states.collect { state ->
        adapter.submitList(state.items)

        binding?.apply {
          loading.visibility = if (state.isLoaded) View.GONE else View.VISIBLE

          when {
            state.items.isEmpty() && state.filterMode == FilterMode.ALL -> {
              empty.visibility = View.VISIBLE
              empty.setText(R.string.msg_empty)
            }
            state.items.isEmpty() -> {
              empty.visibility = View.VISIBLE
              empty.setText(R.string.msg_empty_filtered)
            }
            else -> empty.visibility = View.GONE
          }
        }

        menuMap[state.filterMode]?.isChecked = true
      }
    }

    viewLifecycleOwner.lifecycleScope.launchWhenStarted {
      motor.navEvents.collect { nav ->
        when (nav) {
          is Nav.ViewReport -> viewReport(nav.doc)
          is Nav.ShareReport -> shareReport(nav.doc)
        }
      }
    }

    viewLifecycleOwner.lifecycleScope.launchWhenStarted {
      motor.errorEvents.collect { error ->
        when (error) {
          ErrorScenario.Import -> handleImportError()
        }
      }
    }

    findNavController()
      .getBackStackEntry(R.id.rosterListFragment)
      .savedStateHandle
      .getLiveData<ErrorScenario>(ErrorDialogFragment.KEY_RETRY)
      .observe(viewLifecycleOwner) { retryScenario ->
        when (retryScenario) {
          ErrorScenario.Import -> {
            clearImportError()
            motor.importItems()
          }
        }
      }
  }

  override fun onDestroyView() {
    binding = null

    super.onDestroyView()
  }

  override fun onCreateOptionsMenu(menu: Menu, inflater: MenuInflater) {
    inflater.inflate(R.menu.actions_roster, menu)

    menuMap.apply {
      put(FilterMode.ALL, menu.findItem(R.id.all))
      put(FilterMode.COMPLETED, menu.findItem(R.id.completed))
      put(FilterMode.OUTSTANDING, menu.findItem(R.id.outstanding))
    }

    menuMap[motor.states.value.filterMode]?.isChecked = true

    super.onCreateOptionsMenu(menu, inflater)
  }

  override fun onOptionsItemSelected(item: MenuItem): Boolean {
    when (item.itemId) {
      R.id.add -> {
        add()
        return true
      }
      R.id.all -> {
        item.isChecked = true
        motor.load(FilterMode.ALL)
        return true
      }
      R.id.completed -> {
        item.isChecked = true
        motor.load(FilterMode.COMPLETED)
        return true
      }
      R.id.outstanding -> {
        item.isChecked = true
        motor.load(FilterMode.OUTSTANDING)
        return true
      }
      R.id.save -> {
        saveReport()
        return true
      }
      R.id.share -> {
        motor.shareReport()
        return true
      }
      R.id.importItems -> {
        motor.importItems()
        return true
      }
    }

    return super.onOptionsItemSelected(item)
  }

  private fun display(model: ToDoModel) {
    findNavController()
      .navigate(RosterListFragmentDirections.displayModel(model.id))
  }

  private fun add() {
    findNavController().navigate(RosterListFragmentDirections.createModel(null))
  }

  private fun saveReport() {
    createDoc.launch("report.html")
  }

  private fun viewReport(uri: Uri) {
    safeStartActivity(
      Intent(Intent.ACTION_VIEW, uri)
        .setFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
    )
  }

  private fun shareReport(doc: Uri) {
    safeStartActivity(
      Intent(Intent.ACTION_SEND)
        .setFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
        .setType("text/html")
        .putExtra(Intent.EXTRA_STREAM, doc)
    )
  }

  private fun safeStartActivity(intent: Intent) {
    try {
      startActivity(intent)
    } catch (t: Throwable) {
      Log.e(TAG, "Exception starting $intent", t)
      Toast.makeText(requireActivity(), R.string.oops, Toast.LENGTH_LONG).show()
    }
  }

  private fun handleImportError() {
    findNavController().navigate(
      RosterListFragmentDirections.showError(
        getString(R.string.import_error_title),
        getString(R.string.import_error_message),
        ErrorScenario.Import
      )
    )
  }

  private fun clearImportError() {
    findNavController()
      .getBackStackEntry(R.id.rosterListFragment)
      .savedStateHandle
      .set(ErrorDialogFragment.KEY_RETRY, ErrorScenario.None)
  }
}